Foundations of special relativity
Answers are for parents and teachers.
1
A ship clock measured 16 minutes (proper time) at ship speed 0.6 c. How many minutes does an Earth observer measure?
20
2
A ship of proper length 100 m flies at 0.8 c. What is its length for a station observer in m?
60
3
A spaceship flies at 0.6 c; an Earth observer measures 25 years. How many years does the ship clock show?
20
4
The measured length of a moving rod is 0.6 of its proper length. What is its speed?
0.8 c
5
Why is the speed of light from a moving lamp not c + υ?
By the second postulate the speed of light does not depend on the motion of the source; velocities add by the relativistic law.